RESUMO
BACKGROUND: Using an algorithm by which the effect-site concentration of propofol (esTEC) necessary for BIS level set from information input from BIS monitor and TCI pump is estimated, the effect of remifentanil on esTEC was investigated. METHODS: In 14 abdominal/thoracic surgical patients managed under total intravenous anesthesia with propofol and remifetanil, the distribution of relation between the effect-site concentration of remifetanil and remifentanil esTEC was analyzed in a retrospective manner. RESULTS: While the propofol esTEC decreased in accordance with the increase of the effect-site concentration of remifetanil, the effect-site concentration of propofol esTEC45 for maintaining BIS 45 became within a certain range and with less dispersion when the concentration of remifetanil exceeded 10 ng x ml(-1). CONCLUSIONS: A mutual interaction was observed between propofol esTEC and remifetanil. For anesthetic management with less variation in BIS levels, it was considered that 10 ng x ml(-1) or higher of the effect-site concentration of remifetanil would be necessary.
